public static UtmPt LonLatPtToUtmNad83Pt(LonLatPt lonlat, int zone)
{
double rMajor = 6378137.0;
double rMinor = 6356752.3142450;
double scaleFactor = .9996;
double degreesToRadians = 1.745329251994328e-2;
double factor = degreesToRadians;
double latOrigin = 0;
double lonCenter = ((6 * Math.Abs(zone)) - 183) * degreesToRadians;
//Debug.WriteLine("lonCenter = " + lonCenter);
double falseEasting = 500000;
double falseNorthing = (zone < 0) ? 10000000 : 0;
//Debug.WriteLine(String.Format("rMajor = {0}\n rMinor = {1}\n scaleFactor = {2}\n degreesToRadians = {3}\n latOrigin = {4}\n lonCenter = {5}\n falseEasting = {6}\n falseNorthing = {7}",
// new Object[] {rMajor, rMinor, scaleFactor, degreesToRadians, latOrigin, lonCenter, falseEasting, falseNorthing}));
double temp = rMinor / rMajor;
//Debug.WriteLine("temp = " + temp);
double es = 1 - (temp * temp);
double e = Math.Sqrt(es);
double e0 = e0fn(es);
double e1 = e1fn(es);
double e2 = e2fn(es);
double e3 = e3fn(es);
double ml0 = rMajor * mlfn(e0, e1, e2, e3, latOrigin);
double esp = es / (1 - es);
double ind = (es < .0001) ? 1 : 0;
// double radius = 6370997; // radius of earth in meters
//Debug.WriteLine(String.Format("es = {0}\n e = {1}\n e0 = {2}\n e1 = {3}\n e2 = {4}\n e3 = {5}\n ml0 = {6}\n esp = {7}\n ind = {8}",
// new Object[] {es, e, e0, e1, e2, e3, ml0, esp, ind}));
//Debug.WriteLine("");
double longitude = lonlat.Lon * factor;
double latitude = lonlat.Lat * factor;
double deltaLon = AdjustLon(longitude - lonCenter);
double sinPhi = Math.Sin(latitude);
double cosPhi = Math.Cos(latitude);
double al = cosPhi * deltaLon;
double als = al * al;
double c = esp * cosPhi * cosPhi;
double tq = Math.Tan(latitude);
double t = tq * tq;
double con = 1.0 - es * sinPhi * sinPhi;
double n = rMajor / Math.Sqrt(con);
double ml = rMajor * mlfn(e0, e1, e2, e3, latitude);
//Debug.WriteLine(String.Format("logitude = {0}\n latitude = {1}\n delaLon = {2}\n sinPhi = {3}\n cosPhi = {4}\n al = {5}\n als = {6}\n c = {7}\n tq = {8}\n t = {9}\n con = {10}\n n = {11}\n ml = {12}",
// new Object[]{longitude, latitude, deltaLon, sinPhi, cosPhi, al, als, c, tq, t, con, n, ml}));
UtmPt utmpt = new UtmPt();
utmpt.X = scaleFactor * n * al * (1.0 + als / 6.0 *
(1.0 - t + c + als / 20.0 * (5.0 - 18.0 * t + (t * t) + 72.0 * c - 58.0 * esp))) + falseEasting;
utmpt.Y = scaleFactor * (ml - ml0 + n * tq * (als * (0.5 + als / 24.0 *
(5.0 - t + 9.0 * c + 4.0 * (c * c) + als / 30.0 *
(61.0 - 58.0 * t + (t * t) + 600.0 * c - 330.0 * esp))))) + falseNorthing;
utmpt.Zone = zone;
return (utmpt);
}
public static LonLatPt UtmNad83PtToLonLatPt(UtmPt u)
{
// make a local copy so that we can change values there:
UtmPt utmpt = new UtmPt();
utmpt.X = u.X;
utmpt.Y = u.Y;
utmpt.Zone = u.Zone;
double rMajor = 6378137.0;
double rMinor = 6356752.3142450;
double latOrigin = 0;
double degreesToRadians = 1.745329251994328e-2;
double factor = 57.29577951308231;
double lonCenter = ((6 * Math.Abs(utmpt.Zone)) - 183) * degreesToRadians;
double falseEasting = 500000;
double falseNorthing = (utmpt.Zone < 0) ? 10000000 : 0;
double scaleFactor = .9996;
double temp = rMinor / rMajor;
//Debug.WriteLine("temp = " + temp);
double es = 1 - (temp * temp);
double e = Math.Sqrt(es);
double e0 = e0fn(es);
double e1 = e1fn(es);
double e2 = e2fn(es);
double e3 = e3fn(es);
double ml0 = rMajor * mlfn(e0, e1, e2, e3, latOrigin);
double esp = es / (1 - es);
double ind = (es < .0001) ? 1 : 0;
//Debug.WriteLine(String.Format("es = {0}\n e = {1}\n e0 = {2}\n e1 = {3}\n e2 = {4}\n e3 = {5}\n ml0 = {6}\n esp = {7}\n ind = {8}",
// new Object[] {es, e, e0, e1, e2, e3, ml0, esp, ind}));
//Debug.WriteLine("");
int maxIterations = 6;
utmpt.X -= falseEasting;
utmpt.Y -= falseNorthing;
double con = (ml0 + utmpt.Y / scaleFactor) / rMajor;
double phi = con;
for (int i = 0; ; i++)
{
double delta_phi = ((con + e1 * Math.Sin(2.0 * phi) - e2 * Math.Sin(4.0 * phi) + e3 * Math.Sin(6.0 * phi))
/ e0) - phi;
phi += delta_phi;
if (Math.Abs(delta_phi) <= 1.0e-10) break;
if (i >= maxIterations)
{
throw new Exception("Latitude failed to converge");
}
}
LonLatPt lonlat = new LonLatPt();
if (Math.Abs(phi) < (Math.PI / 2))
{
double sinPhi = Math.Sin(phi);
double cosPhi = Math.Cos(phi);
double tanPhi = Math.Tan(phi);
double c = esp * (cosPhi * cosPhi);
double cs = (c * c);
double t = (tanPhi * tanPhi);
double ts = (t * t);
con = 1.0 - es * (sinPhi * sinPhi);
double n = rMajor / Math.Sqrt(con);
double r = n * (1.0 - es) / con;
double d = utmpt.X / (n * scaleFactor);
double ds = (d * d);
lonlat.Lat = phi - (n * tanPhi * ds / r) * (0.5 - ds / 24.0 * (5.0 + 3.0 * t +
10.0 * c - 4.0 * cs - 9.0 * esp - ds / 30.0 * (61.0 + 90.0 * t +
298.0 * c + 45.0 * ts - 252.0 * esp - 3.0 * cs)));
lonlat.Lon = AdjustLon(lonCenter + (d * (1.0 - ds / 6.0 * (1.0 + 2.0 * t +
c - ds / 20.0 * (5.0 - 2.0 * c + 28.0 * t - 3.0 * cs + 8.0 * esp +
24.0 * ts))) / cosPhi));
}
else
{
lonlat.Lat = (Math.PI / 2) * Math.Sign(utmpt.Y);
lonlat.Lon = lonCenter;
}
lonlat.Lon *= factor;
lonlat.Lat *= factor;
return (lonlat);
}